<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script>
        // 动物--->人--->--->老师--->坏老师
		function Animal() {
			this.gender ="male";
		}
		Human.prototype = new Animal();
		Human.prototype.constructor = Human;
		
		function Human() {
			this.actionWay = "走路";
		}
		Teacher.prototype = new Human();
		Teacher.prototype.constructor = Teacher;
		function Teacher() {
			this.skill = "教书";
		}
		
		BadTeacher.prototype = new Teacher();
		BadTeacher.prototype.constructor = BadTeacher;
		function BadTeacher() {
			this.name = "叶坏";
		}
		
		var t = new BadTeacher();
		console.log(t);
    </script>
</head>
<body>

</body>
</html>